ISLET CELL BIOLOGY CORE: Director - F. Matschinsky It is the purpose of this core to assist investigators who currently study or have plans to study independently or collaboratively various aspects of pancreatic islet cell biology. In order to accomplish this goal the Core provides four services. First, it will perform extra corporal phenotyping of the endocrine pancreas of mouse and rat using the intact isolated perfused or minced perifused pancreas. Second, it will isolate, culture, and functionally assess pancreatic islets of rat and mouse including batch incubations, perifusions, respirometry, measurements of Caj++, the P-potential (ATP, ADP, AMP and Pi) and other metabolites, hormone contents and release. Third, it maintains a broad and well characterized stock of transformed islet cells, grows large batches of such cells or generates pseudo islets by embedding such cells into agarose beads for dynamic studies of metabolism and hormone release. Fourth and most important, it provides in depth consultation and helps develop strategies how to use the services of the core optimally or will attempt to modify available technologies to solve particular problems. The islet cell resource permits the broad application of approaches which are too labor intensive and technically too demanding to be maintained by the average single laboratory. The core offers training to those who have the resources and wish to establish approved procedures and technologies in their own laboratory. Costs are reduced through a large scale operation. The Core functions thus as a research support and educational unit for an active group of investigators with somewhat diverse interests, and fosters interdisciplinary islet research.